The Nb Rat Prostatic Adenocarcinoma model was initially described by Dr. R. L. Noble of the Vancouver Cancer Institute. This laboratory unit has been evaluating its usefulness to study prostatic adenocarcinoma. The model has been classified histologically, histochemically and biochemically. There are many tumor types including androgen insensitive and androgen sensitive types. Single agent chemotherapy, as well as combination chemotherapy has been evaluated in treatment of the androgen insensitive tumor type. The most efficacious single agents have been Cis-platinum and Cyclophosphamide. The most effective combination agents have included Cis-platinum, Adriamycin and Cyclophosphamide. With regard to treatment of the androgen sensitive type, hormonal therapy has included castration, and or administration of 17-beta-estradiol. The results revealed a decrease in tumor volume as compared to the controls, which is statistically significant. However, in none of these animals has the tumor undergone complete tumor regression, nor has there been any decrease in the number of metastasis identified. Combining hormonal therapy with combination or single agent chemotherapy, there is a dramatic response in terms of complete tumor regression, as well as, decreased tumor metastasis especially when utilizing either Cis-platinum or Cyclophosphamide alone or in combination. It appears preliminarily, that the use of hormonal manipulation via castration, plus combination chemotherapy, has a synergistic effect with a more marked decrease in tumor growth rate than with either modality employed alone. Continued work with utilizing combination chemotherapy, with or without hormonal therapy in the androgen insensitive, as well as androgen sensitive tumors, is being conducted. Finally, work has been initiated evaluating the usefulness of androgen receptors in these tumors to determine whether or not they are hormonally sensitive and will respond to androgen manipulation.